Lumbosacral Transitional Vertebrae Predict Inferior Patient-Reported Outcomes After Hip Arthroscopy

Abstract

Background: While the association between spinal disease and hip arthroplasty outcomes has been well studied, there is less known about the effect of spinal pathology in hip arthroscopy (HA) outcomes. Lumbosacral transitional vertebrae (LSTV) are anatomic variations where caudal vertebrae articulate or fuse with the sacrum or ilium. Hypothesis: LSTV can lead to inferior outcomes after HA for treatment of femoroacetabular impingement. Study Design: Cohort study; Level of evidence, 3. Methods: We retrospectively reviewed the prospectively collected Hip Arthroscopy Database at our institution for patients with LSTV who underwent HA between 2010 and 2017. A total of 62 patients with LSTV were identified and then matched to controls. Patient-reported outcome measures (PROMs) were collected, including the modified Harris Hip Score, Hip Outcome Score–Activities of Daily Living, Hip Outcome Score–Sports, and the 33-item International Hip Outcome Tool. They were collected at 4 time points: preoperatively and 5 to 11 months, 12 to 23 months, and 24 to 35 months postoperatively. Longitudinal analysis of the PROMs was done using generalized estimating equation modeling. Additionally, alpha angles were measured from preoperative radiographic data. Results: Preoperatively, there was no significant difference between patients with and without LSTV on 3 of the 4 PROMs; however, patients with LSTV did have significantly lower preoperative scores than controls for the Hip Outcome Score–Activities of Daily Living ( P = .029). Patients with LSTV reported significantly lower scores on all 4 PROMs at each postoperative time point. Radiographic data showed no significant difference in alpha angles across cohorts. When LSTV were compared by Castellvi type, types 3 and 4 tended to have lower scores than types 1 and 2; however, these comparisons were not significant. Conclusion: The data support our hypothesis that HA has less benefit in patients with LSTV as compared with patients without LSTV. In patients with LSTV, careful evaluation of the anomaly is recommended to help guide surgical counseling and manage expectations.

Limited lumbopelvic mobility does not influence short-term outcomes after primary hip arthroscopy: a propensity-matched controlled study

“…Limited spinal mobility remains a poorly recognized clinical entity in hip preservation. In a critical evaluation of the current literature, the majority of studies drew comparisons between patients with lumbar spine pathology or anatomic variants against a control group of patients without known lumbar spine disease [ 6 , 7 , 16 ]. These studies have demonstrated that preexisting lumbar pathology may adversely affect outcomes after hip arthroscopy.…”

“…More recently, Heaps et al . [ 16 ] reported that patients with lumbosacral transitional vertebrae (LSTV) had less benefit after hip arthroscopy as demonstrated by lower patient-reported outcome scores (PROs) 24–35 months postoperative compared to patients without LSTV. In their paper they proposed the importance of lumbosacral motion loss on outcomes in hip arthroscopy due to the possibility of residual FAI even after surgical correction.…”

Editorial Commentary: Lumbosacral Anatomy and Mechanics Influence Femoroacetabular Impingement Syndrome and Surgical Outcomes: The Hip Bone Is Connected to the Back Bone

“…These findings differ from other reports in the literature, although this difference is hardly irreconcilable. Heaps et al 18 recently reported less benefit of hip arthroscopy in patients with LSTV, with patients with LSTV having significantly lower patient-reported outcomes measures 5 to 11 months postoperatively, 12 to 23 months postoperatively, and 24 to 35 months postoperatively versus patients without LSTV. We would certainly benefit from further study to understand why patients with LSTV did worse than that of the current study by Luo et al, but it is important to note that a significantly greater proportion of patients with LSTV had Castellvi type 3 or 4 on this study (52% of patients included with LSTV) compared with the study by Luo et al (7.7% of patients included with LSTV).…”

“…We would certainly benefit from further study to understand why patients with LSTV did worse than that of the current study by Luo et al, but it is important to note that a significantly greater proportion of patients with LSTV had Castellvi type 3 or 4 on this study (52% of patients included with LSTV) compared with the study by Luo et al (7.7% of patients included with LSTV). 17,18 This difference between cohorts may highlight the importance of lumbosacral motion loss on hip outcomes. This is in line with biomechanical and finite element studies that show that even with more stiffness, low-grade transitional vertebrae do retain some degree of mobility that may not be present in those with fused vertebrae.…”

Hips 2021

“…Much additional clinical hip arthroscopy research has sought to identify other factors that might predict surgical outcomes, including general patient characteristics, preoperative hip anatomy, and preoperative or early postoperative pain or PROM levels. 5,11,13,[17][18][19][20] Most of these studies have been retrospective in design, so they identify associations that would need to be verified as truly predictive in future prospective studies. As New York Yankee great Yogi Berra is reported to have said, ''It's tough to make predictions, especially about the future.''…”